Tape automated bonding is becoming the choice for packaging integrated circuits having high lead count. In this process, thin copper or metal films are etched to define thin film beam conductors which are bonded to the chip contact pads and provide connections to associated printed circuit boards or other circuits. The thin conductive film, in certain instances, has been bonded to an insulating tape to provide testability, transportability and structural rigidity to the thin film conductors.
The format for the thin metal film or thin film layered tape, includes an elongated tape with sprocket holes for indexing the tape as the semiconductor chip is bonded to the thin leads and then advanced to various processing stations for encapsulation, testing and the like. The tapes have widths ranging from 8 to 70 millimeters and are provided on reels or strips. The tape portions which do not form leads for the integrated circuit package are discarded when the integrated circuit package is severed from the tape. Generally, the discarded materials represent a significant cost of packaging.